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Epson Research and Development
Vancouver Design Center
S1D13503
MC68340 Interface Considerations
X18A-G-004-04
Issue Date: 01/01/30
2 MC68340 MPU INTERFACE
The following sections provide the necessary settings and equations to complete the interface between the S1D13503 and
the MC68340 microcontroller.
Figure 1: MC68340 MPU Interface Block Diagram
2.1 MC68340 Setup
For the purpose of this example, the following conditions apply:
The internal chip select signal CS3 of the MC68340, along with external DSACK1 response, is employed to access the
S1D13503. Direct mapping of the I/O with starting address at 00000000h, and 128Kbytes of display memory with starting
address 00020000h are also used.
1.
CS3 with 256kbyte block size - starting address at 00000000h and ending address at 0003FFFFh
2.
External DSACK1 response - 16-bit port
3.
Don’t care Function Codes and with CPU space access
4.
Both read and write accesses are allowed
Settings for the Address Mask register and Base Address register for the above conditions are:
058h - 05Bh
= 0003FFFFh
Address Mask register
05Ch - 05Fh
= 000000F5h
Base Address register
V
CC
4.7k
Ω
10k
Ω
V
CC
V
CC
VD0-VD3
VD13
A0
A10-A17
MEMCS#
IOCS#
BHE#
AB0-AB19
DB0-DB15
MEMR#
MEMW#
IOR#
IOW#
READY
CS3
SIZ0
A0-A19
D0-D15
AS
R/W
DSACK1
MC68340
PAL
S1D13503
RESET
RESET
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